Observations on the Influence of Temperature Of Second Stage Juveniles (Meloidogyne Spp.) in the Absence of the Host Plant

Abstract

Abstract The knowledge of root-knot nematodes behavior in different habitats and especially the knowledge of their reaction to major ecologic factors (humidity, temperature) are important for the assessment of pathogen potential in a specific area, being at the same time an important criterion for understanding the behavior towards host plants. The temperature is the most important factor, not just in the development of the entire biological cycle of root-knot nematodes, but at the same time it also affects their distribution, spread and survival under thermic stress conditions (excessive heat or cold). Alongside with the water and oxygen, the temperature is the triggering factor of hatching and running all stages until the adult stage. The articles aims to determine the survival of juveniles stages for Meloidogyne species, in the absence of host plants, and by exposing second stage juveniles to different temperatures. The juveniles survival and mobility decreases quite much at relative low temperatures (4°C and 10°C). Forward movements, mobility, hatching and lifetime were accentuated at higher temperatures (20°C) for a few weeks, so that after a period to decrease drastically (in 10 and 12 week) for the species considered for the study.